Prismalo Aquarelles were the first water-soluble colored pencils on the market, and have been out since 1931. Prismalos are produced in Geneva. Prismalos have been used by generations of school children, amateur, and professional artists. Their leads are harder, and thinner than that of Supracolors, being 3mm in diameter. The pencils are hexagonal, and they have exteriors that match the core color. There are color numbers, but no names.